Double stacker system and method

ABSTRACT

A system and method for stacking two bulk bags one on top of the other on a pallet, the method comprising controlling a pallet feeder into providing a pallet; filling a first bag with a first amount of product on the pallet and sealing the first bag; filling a second bag with a second amount of product, and depositing the second bag filled with the second amount of product on top of the first bag on the pallet; and straightening the bags on the pallet; wherein these steps of controlling, filling the first and second bags, and straightening are controlled by a programmable controller, the programmable controller selecting the first amount to be fed to the first bag supported by the pallet and, selecting the second amount to be fed to the second bag.

FIELD OF THE INVENTION

The present invention relates to bulk shipping. More particularly, the invention pertains to a method and a system for palletizing bags of products, such as peat moss in bulk.

BACKGROUND OF THE INVENTION

Standardly, peat moss bulk louse bags are produced manually, requiring multiple operators.

When the volume of production increases, there is a need for a method and a system forming peat moss bulk louse bags automatically with a reduced number of operators.

SUMMARY OF THE INVENTION

More specifically, in accordance with the present invention, there is provided a system for stacking two bulk bags one on top of the other on a pallet, comprising a pallet feeder; a first filling station, receiving a pallet from the pallet feeder and a first amount of product to be bagged, the first filling station comprising hooks for securing a first bag with an open mouth above the pallet, and filling the first bag with the first amount of product on top of the pallet; a second filling station, the second filling station comprising hooks for securing a second bag with an open mouth, the second filling station receiving a second amount of the product to be bagged, filing the second bag with the amount of the product and filing the second bag, receiving the pallet with the first bag filled with the first amount of product and sealed at the first filling station, and depositing the second bag filled with the second amount of product and sealed on top of the first bag; a bag straightener station, receiving the pallet supporting the second bag on top of the first bag from the second filling station, the bag straightener station straightening the bags on the pallet; and a programmable controller; wherein the programmable controller operates the pallet feeder into sending a pallet to the first filling station when the first filling station is empty, selects the first amount to be fed to the first bag supported by the pallet at the first filling station, operates the first filling station to send the pallet supporting the first bag filled with the first amount of product to the second filling station when the second filling station is empty, selects the second amount to be fed to the second bag at the second filling station, operates the first filling station to send the pallet with the first bag filled with the first amount of product and sealed at the first filling station to the second filling station when the second bag is filled, and the second filling station to send the pallet supporting the first bag filled with the first amount of product and the second bag filled with the second amount of product on top of the first bag to the bag straightener station when the bag straightener station is empty.

There is further provided a method for stacking two bulk bags one on top of the other on a pallet, comprising controlling a pallet feeder into providing a pallet; filling a first bag with a first amount of product on the pallet and sealing the first bag; filling a second bag with a second amount of product, and depositing the second bag filled with the second amount of product on top of the first bag on the pallet; and straightening the bags on the pallet; wherein the controlling, the filling of the first and second bags, and the straightening are controlled by a programmable controller, the programmable controller selecting the first amount to be fed to the first bag supported by the pallet and selecting the second amount to be fed to the second bag.

There is further provide A bag straightener, comprising vertical walls; and a top compression plate; wherein the walls are controlled by cylinders into moving from an opened position to receive a bag, into an enclosure position around the bag; and the compression plate is then actuated by a compaction cylinder operating a compaction shaft supporting the compression plate into compressing the bag in the enclosure formed by said walls.

Other objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of specific embodiments thereof, given by way of example only with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 are a) a front perspective view and b) a back perspective view of a system according to an embodiment of an aspect of the present invention;

FIG. 2 show a) a pallet feeder of the system of FIG. 1; b) a pallet pusher of the pallet feeder of FIG. 2 a; c) arms of the pallet feeder of FIG. 2 a; d) details of the pallet pusher of FIG. 2 b; e) the magazine of the pallet feeder of FIG. 2 a;

FIG. 3 show a) a first filling station of the system of FIG. 1; b) details of the first filling station of FIG. 3 a.

FIG. 4 shows hooks holder of filling stations of the system of FIG. 1;

FIG. 5 shows station 3 of the system of FIG. 1;

FIG. 6 shows the second filling station of the system of FIG. 1;

FIG. 7 shows a) a bag straightener station of the system of FIG. 1; b) a detail of the bag straightener station showing a linear displacement of walls; c) a detail the bag straightener station showing a moving/closing walls structure; d) a detail of the bag straightener station, showing a top compaction structure; e) a detail of the bag straightener station, showing a back wall compaction structure on a ISO view; f) a detail of the bag straightener station showing a back wall compaction structure on back view;

FIG. 8 show a) a batching supply; b) a side view of the batching supply showing conveyors and level sensors; c) a top view of the batching supply showing the inside of the supply; d) details of the batching supply showing adjusting gates and sensors;

FIGS. 9 a-9 h show panel view windows to control the system;

FIG. 10 show a) a bag; b) double stacked bags; and

FIG. 11 shows an operator panel.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

As illustrated in FIG. 1, the system comprises a batching supply (R) and stations automatically and sequentially building a pallet supporting two bulk bags stacked one on top of the other, as controlled by a programmable controller (PLC) (not shown).

Best seen in FIG. 8, the batching supply (R) receives the product to be bagged and feeds a first and a second filling stations, namely stations 2 and 4, by a conveyor 70 and 80 respectively.

Station 1, which will be discussed hereinbelow in relation to FIG. 2, is a pallet feeder, providing a pallet under a first empty bag. Station 2 is a first filling station, for filling a first bag on the pallet (see FIG. 3). Station 3 prepares the first bag (i.e. bottom bag of the stacking) to receive a second bag (i.e. top one bag of the stacking) (see FIG. 5) to. Station 4 is a second filling station, for feeding the second (top) bag (FIG. 6). Finally, station 5 is a bag straightener station, where the stacked bags are straightened and compressed on the pallet (FIG. 7).

The batching supply (R) is supported by a structure 92 bolted to the frame 31 of the station 3 (see FIGS. 5 and 8 a).

The batching supply (R) is fed with the product the be bagged, for example by a conveyor dumping in a small bidirectional conveyor 90 to select in which side of the divider plate 91 to dump the product, as controlled by the PLC (see FIG. 8 b).

The batching supply (R) is used to pre calibrate the amount of product in the bags. The system as illustrated herein is able to make two different bag volumes: 55 and 75 cu foot bags. In this example, the batching supply (R) is divided into two by the divider plate 91 (FIG. 8 b) located between the conveyors 70 and 80 of filling stations 2 and 4 respectively. Capacitive sensors 71, 72, 73 and 81, 82, 83 (see FIGS. 8 b and 8 d) staked one above the other on each side of the batching supply (R), are used to monitor the amount of product conveyed to the respective bags. For example, bottom sensors 71, 81 indicate a low level, mid ones 72, 82 indicate a level for the 55 cu foot bags and the top ones 73, 83 indicate a high level, i.e. for the 75 cu foot bags. The volume in the bags is controlled by the PLC with a feeding timer. A blower (not shown), controlled by a pneumatic valve controlled by the PLC may be used to clean the sensors to make sure the sensors are not incorrectly on when they are only dirty. Adjusting gates 74, 84 at the exit of conveyors 75, 85 allow leveling the thickness of product, so that the volume at each second is equal. The operator controls the feeding timer of each station 2, 4 through an interface (FIG. 11).

FIG. 2 show details of station 1. Station 1 feeds the first filling station 2 with a pallet, one at the time.

Station 1 is in automatic mode as programmed by the PLC. The operator has access to an operator panel comprising different windows, for selection of a specific window (FIG. 9 a), automatic screen (FIG. 9 b), manual screen bidirectional motion (FIG. 9 c), manual screen unidirectional motion (FIG. 9 d), timers screen (FIG. 9 e), log of input/output of PLC (FIG. 9 f), alarms (FIG. 9 g) and help screen (FIG. 9 h).

Station 1 comprises a frame 10 supporting a pallet pusher best seen in FIGS. 2 b and 2 c. The PLC controls lifter arms 12 of the pallet pusher of station 1, so that the lifter arms 12 move down to leave a bundle of pallets on rails 19. The lifter arms 12 open and elevate a first pallet (not shown) from the bundle before they close again on the bundle. A third step is to lift back the pallet bundle to give room to the first pallet to move forward. When the pallet pusher receives instruction from the PLC to move forward the pallet, a chain 18 is activated (see FIG. 2 d), by an electric motor with a gear box to decrease the chain speed to the same speed as the roller conveyor 22 of station 2. A gusset 13 welded on the chain 18 moves the pallet forward to push it towards station 2 to a front stop sensor 14 of the pallet pusher (see FIGS. 2 b, 2 d). When the pallet is seen in station 1, the PLC gives a reverse command to the pallet pusher and the pallet pusher stops at a back sensor 15. After that step, station 1 awaits for another order for a new pallet, in a waiting mode.

The frame 10 of the pallet feeder is a totally enclosed pallet magazine. It is enclosed by two doors 101 at the back (see FIG. 2 a), which also keep the pallet bundle straight. If an operator needs to add a pallet, the operator has to push a button to let know the PLC. Then, the lifter arms 12 move down to leave the bundle on the rails 19. The lifter arms 12 open to give room to the operator to place the pallet bundle in it. The operator is then able to open a door latch 103 and open the doors 101. The door latch 103 is provided with a sensor 102 (see FIG. 2 e) to let know the PLC to stop the operation of that station 1 for safety.

Station 2, in automatic mode, puts a pallet on a pallet conveyor 22 (see FIG. 3 a). The operator, working on a catwalk, takes a bag on a bag platform and attaches it on hooks 25 and 28 of station 2 (FIG. 3 b). As illustrated in FIG. 10 a, the bags are made with an open mouth 102 to fill the bags and comprise four straps 101, one on each top corner of the bags. The operator pushes each strap 101 into one of two front hooks 28 and two rear hooks 25 to hold the bag in station 2.

FIG. 4 shows details of the hooks holding the bags. A hook head 282 is bolted on a frame, such as a piece of steel flat bar 280. The hook head 282 is swiveled on one axis of about 100 degrees rotation. An air cylinder 281 is fixed on a first end thereof on the frame 280 and on a rod end thereof on the hook head 282. Thus, when the air cylinder 281 is retracted, the hook head 282 is opened and frees the straps of the bag. When the air cylinder 281 is fully extended, the hook head 282 is closed, thereby securing the straps of the bag. A flexible piece of UHMW 283 may be provided for closing the opening of the hook head 282, so that the strap needs only by pushed on the piece 283 to be made to enter the hook head 282 without having to open the hook head 282.

The front hooks 28 are fixed to the lifting mouth 26 of station 2 (see FIG. 3 b). In contrast, the back hooks 25 are movable, by a mover 29 actuated by an air cylinder 24, from a front position to help the operator to attach the straps in the hooks, to a back position to lift the bags straight and not choke the discharge of product in the bag.

When the bag is installed on the hooks 25, 28 as described hereinabove, the operator opens the mouth 26 of station 2 and installs the bag thereon. The mouth 26 comprises air clamps 27 (see FIG. 3 b) to hold the bag mouth in place. When the bag is in place on the feeder mouth 26, the operator presses a button 1A on the control interface (FIG. 11), thereby instructing the PLC to close the clamps 27 to hold the bag mouth, thus preventing the product from leaking out of the bag and the dust from blowing out from the bag. At this time, when the button is pushed, the supply (FIG. 8 a) feeds the bag with a conveyor 70 during an amount of time controlled by the PLC according the value the operator previously entered in the control panel (see FIG. 9 e timer screen). Between the shoots of conveyor 70 and the filler mouth 26, a flexible tube (not shown) may be provided to flow directly in the bag and prevent the leaks.

During the filling time, after preselected timer (entered in the machine control panel by the operator), the lifting mouth filler 26 (see FIG. 3 b) rises and gets down automatically, under action of the up/down cylinder 21 (best seen in FIG. 3 a) to shake the bag and the product in it to place the product to make sure the bag is as stable as possible. Guiding plate 23 prevents the bag from bulging, so that the bag takes an overall square or rectangular shape footprint corresponding to the pallet.

At the end of filling time, the clamps 27 open to let the operator attach the mouth with the rope of the bag, to make sure no contaminants enter the bag during transport or before his utilization.

When the bag is thus sealed, the operator pushes a button 1 b (see FIG. 11: bag tied ready to exit from station 1) to drop the bag on the pallet (not shown) sitting on the conveyor 22. When the next station, station 3, comes empty, i.e. without any pallet on its conveyor 32, the pallet with the first bag thereon is moved forward to station 3 (FIG. 5). When the station 2 is emptied, the operator is able to put another bag on the filler and start back the filling of a bottom bag again.

At station 3, a positioning hole is made on the top surface of the bottom bag before the top bag is put sitting thereon. A pallet with a filled first bag as described hereinabove comes from station 2 (FIG. 3). The conveyors 22 of station 2 and 32 of station 3 run until a sensor indicates the pallet is centered on station 3. As shown in FIG. 5, guiding plates 33 are provided to square the bag again to make sure the load is not overflowing the pallet. When the pallet is stopped and centered, a compression cylinder 34 moves a plate down to form a concave area in the middle of the bag, intended to accommodate the bottom of the second filled bag so that the second filled bag, when stacked on top of the first filled bag, sits on top of the first filled bag in a stabilized equilibrium. The plate goes down until hitting a sensor 36, 37 corresponding to the bag size as discussed hereinabove. It stops in that position for a couple of seconds and after that timer, the plate is retrieved back to a lifted position indicated by a sensor 35. That timer is in the panel view and it can be changed by the operator. When the next station, station 4, comes empty, i.e. without any pallet on its conveyor 42 (see FIG. 6), the pallet is moves forward to station 4. The conveyors 32 and 42 run to move the pallet from station 3 to station 4 until a sensor indicates arrival at station 4, then the conveyors 32 and 42 stop.

Station 4, described in relation to FIG. 6, is provided to fill a second bag, without a pallet under it.

Station 4, in automatic mode, is ready, waiting the operator to install an empty bag on hooks 45 and 48. The operator takes straps 101 and put them on the hooks 45 and 48 on the filling mouth 46 of station 4, thereby hanging the second bag ready for filling up. Then the operator pushes a button on the interface (see button bag ready to fill, see FIG. 11), thereby triggering the supply (FIG. 8) to start and fill the bag with the conveyor 80. Between the shoots of conveyor 80 and the filler mouth 46 of station 4 (see FIG. 6), a flexible tube (not shown) may be provided to flow directly in the bag and prevent leaks. At station 4, no pallet is on the conveyor 42 because the pallet of the station 3 is coming later in the process.

Hooks 45, 48, similar to those described in relation to FIG. 3 and best seen in FIG. 4, are used to secure the straps of the second bag. Front hooks 48 are fixed to the lifting mouth 46 of unit 4. Back hooks 45 are movable, using back hook mover 49 actuated by an air cylinder 44, between a front position to help the operator to attach the straps in the hooks and a back position to lift the bag straight and not choke the discharge of product in the bag. When the bag is installed on the hooks 45, 48, the operator opens the mouth 46 to install the bag on the filling mouth 46. The mouth 46 comprises air clamps 47 on each side. These clamps 47 are closed by the operator when he has finish to place the bag mouth on the feeder mouth 46, to hold the bag mouth in place, prevent the product from leaking out and the dust from blowing out from the bag, when the operator pushes on the button close clamps of the operator interface (Button 2A, see FIG. 11). When the bag is in place at the station 4 (FIG. 5), the operator pushes a button to notify the PLC that the second bag is ready to fill. Then, the batching supply (R) (FIG. 8 a) feeds the second bag with the conveyor 80 during an amount of time controlled by the PLC according to a value previously entered by the operator in the control panel. Between the shoots of conveyor 80 and the filler mouth 46, have a flexible tube (not shown) may be provided to flow directly in the bag and prevent the leaks.

During the filling time, after a preselected timer (entered in the machine control panel by the operator), the lifter frame 41 of the mouth filler 46 rises and gets down automatically to shake the second bag and the product therein to distribute the product in the bag and ensure stability of the bag. Guiding plates 43 are provided to hold the bag into a generally square shape footprint corresponding to the pallet.

At the end of filling time, clamps 47 open to let the operator attach the mouth of the bag with a rope, to prevent ingress of contaminants during transportation or before utilization.

When the bag is thus sealed, the operator pushes a button 2 b on the operator interface (FIG. 11: Bag tied, elevator ready to go up), thereby activating the lifter frame 41 to go up and pass in front of a sensor indicating a stop position. At that time, the PLC is instructed that it is safe to move the pallet from the conveyor 32 of station 3 (FIG. 5) to station 4 on the conveyor 42, beneath the second full bag, lifted in a waiting position by the lifter frame 41. The pallet with the first bag thereon is then stopped with its load centered on conveyor 42 at station 4 beneath the second full bag. The PLC orders dropping of the second bag on the pallet sitting on the conveyor 42 and opening of the hooks to free the second bag on top of the first bag, thereby forming a double staked pallet, as shown in FIG. 10 b. The first bag 103, filled at station 2, is topped by the second bag 104, filled at station 4.

When the next station, i.e. station 5 shown in FIG. 7, comes empty, i.e. without any pallet on its conveyor 42, the pallet with the double staked pallet is moved to station 5. When station 4 is emptied, the operator is able to put another bag on the filler and start back the process again for filling next second bag for another double staked bag.

Station 5 (see FIG. 7) is used to straighten and square the bags on the pallet, so that the double bag is typically no more than 42″×50″ and preferably of the same size as the pallet (typically 40″×48″). Four walls are made to enclose the bags on the pallet, and after the walls are in place, a compression plate compresses the bags for stability.

Station 5, like the rest of the system, is controlled by the PLC. At a waiting position, the walls of station 5 are positioned at an opened position to leave maximum room for the pallet coming from station 4 to enter station 5 conveyed by the conveyor 52. When a pallet is ready on the conveyor 42 of the station 4 (FIG. 6), the PLC checks that the conveyor 52 of station 5 can move the pallet forward. If there is no pallet on the conveyor 52 of station 5, the conveyors 42 and 52 are activated to run and move the pallet forward. When the load is centered on the conveyor 52 of station 5, the conveyors 42 and 52 are stopped.

At that time, the walls of unit 5 are put into action, powered by hydraulic power. The walls are moved by step by step displacement toward the pallet. A structure 55 of mobile walls 583, 584 and 588 is moved to place walls on three sides of the pallet sitting on the conveyor 52 until a linear moving frame 56 passes in front of a sensor and stops it (FIG. 7 a). The structure 55 is bolted on the frame 56 which is actuated by a hydraulic cylinder. As best seen in FIG. 7 b, the linear displacement of the frame 56 (see FIG. 7 a) is controlled by guiding rails 561 and a hydraulic cylinder 562, so that rolling bearing wheels of the moving walls are turning in the guiding rails 561 to make sure the displacement is straight and the walls are strong to hold the load.

In a second time, two opposite moving walls 583, 584 are made to close on the load, under action of a pivot tubing system 581 (see FIG. 7 f) and a hydraulic cylinder 582. Using a pivot allows synchronizing the walls together to make sure the load is not pushed or moved more on one side than on the other side, and thus that the load is equally supported and stable.

As best seen in FIG. 7 f, the cylinder 582 extends or retracts to rotate the pivot 581, which in turn, via timing bars 585, pulls or pushes timing bars 585 to move (linearly) in/out two opposite side walls 583 and 584, slipping on a linear guide 587. The pivot 581 with the timing bars 585 make the two walls 583 and 584 synchronized, so that, when a load is centered between the walls 583 and 584 and the walls 583 and 584 begin to move toward the load, they contact the load at the same time and push the bags on each side equally.

When the three walls 583, 584 and 588 are in place around three sides of to the bags, the wall 532 opposite the wall 588, supported by a structure 53 bolted on the main structure frame 51 of station 5 as shown in FIG. 7 a, is activated. This wall 532 is moved by two strong cylinders 533 (FIG. 7 e). These cylinders 533 are pinned in some high adjustment 531 allowing adjusting the level of the cylinders in relation to the weight distribution in the stacked bags. The wall 532 is pushed towards the double stack bags until triggering a stop a sensor, at which point the four walls form a square enclosure around the bags.

In a final step, compression is achieved by a top plate 542 (FIG. 7 d), in a similar way as discussed in relation to station 3 (FIG. 5). FIG. 7 d shows details of the top cylinder plate structure 54 used to compress the bags in the enclosure formed by the four walls as described hereinabove. The top plate structure 54 is bolted on the frame 51 of station 5 and supports a compaction cylinder 543 actuating the compaction plate 542 through a compaction shaft 544 to give compaction strength to the plate 542. Compaction bushing 545 guides the shaft 544 to ensure the shaft 544 have a straight displacement and the compaction plate 542 has no bending or unbalanced pushing action on the bags.

With the four walls 532, 583, 584 and 588 in place as just described, the compaction plate 542 is moved downward to compress the bags, until triggering a bottom sensor, when the plate 542 is stopped for a time, controlled in the PLC by the panel view. The operator can change that timer manually in the panel view to adjust the time the plate 542 remains on top of the bags.

When that timer is done, the four walls 532, 583, 584 and 588 and the plate 542 are withdrawn away from the bags, leaving compressed, straight bags on the pallet. The pallet with the bags is then moved on conveyor 52 to a wrapping machine.

Although the present invention has been described hereinabove by way of embodiments thereof, it may be modified, without departing from the nature and teachings of the subject invention as described herein. 

1. A system for stacking two bulk bags one on top of the other on a pallet, comprising: a pallet feeder; a first filling station, receiving a pallet from said pallet feeder and a first amount of product to be bagged, said first filling station comprising hooks for securing a first bag with an open mouth above said pallet, and filling the first bag with the first amount of product on top of said pallet; a second filling station, said second filling station comprising hooks for securing a second bag with an open mouth, said second filling station receiving a second amount of the product to be bagged, filing the second bag with the amount of the product and filing the second bag, receiving the pallet with the first bag filled with the first amount of product and sealed at said first filling station, and depositing said second bag filled with said second amount of product and sealed on top of said first bag; a bag straightener station, receiving the pallet supporting the second bag on top of the first bag from said second filling station, said bag straightener station straightening the bags on the pallet; and a programmable controller; wherein said programmable controller operates said pallet feeder into sending a pallet to said first filling station when said first filling station is empty, selects said first amount to be fed to said first bag supported by the pallet at said first filling station, operates said first filling station to send the pallet supporting the first bag filled with the first amount of product to said second filling station when said second filling station is empty, selects said second amount to be fed to said second bag at said second filling station, operates said first filling station to send the pallet with the first bag filled with the first amount of product and sealed at said first filling station to said second filling station when said second bag is filled, and said second filling station to send the pallet supporting the first bag filled with the first amount of product and the second bag filled with the second amount of product on top of the first bag to said bag straightener station when said bag straightener station is empty.
 2. The system of claim 1, comprising a batching supply, said batching supply feeding said first filling station with said first amount of product and said second filling station with said second amount of product.
 3. The system of claim 1, wherein said pallet feeder moves a pallet to said first feeding station when instructed by said programmable controller.
 4. The system of claim 1, further comprising a compression station, receiving the pallet supporting the first bag filled with the first amount of product and sealed at said first filling station, said compression station compacting said first bag, said programmable controller operating said compression station into sending the pallet supporting the first bag to said second filling station when said second filling station is empty of a pallet.
 5. The system of claim 1, wherein said bag straightener station comprises: walls; and a compression plate; wherein said walls are controlled by said programmable controller into moving from an opened position, to receive the pallet supporting the first and second bags from the second filling station, to an enclosure position around the pallet supporting the first and second bags; and said compression plate is then controlled by said programmable controller to compress the bags in the enclosure formed by said walls.
 6. A method for stacking two bulk bags one on top of the other on a pallet, comprising: controlling a pallet feeder into providing a pallet; filling a first bag with a first amount of product on the pallet and sealing the first bag; filling a second bag with a second amount of product, and depositing the second bag filled with the second amount of product on top of the first bag on the pallet; and straightening the bags on the pallet; wherein said controlling, filling the first and second bags, and straightening are controlled by a programmable controller, the programmable controller selecting the first amount to be fed to the first bag supported by the pallet and, selecting the second amount to be fed to the second bag.
 7. The method of claim 6, comprising feeding said filling of the first bag and said filling of the second bag through a batching supply controlled by the programmable controller.
 8. The method of claim 6, wherein said straightening the bags on the pallet comprises centering the pallet supporting the second bag on top of the first bag within vertical walls, controlling the walls into moving from an opened position to an enclosure position around the pallet supporting the first and second bags; and activating, by the programmable controller, compression of the bags supported by the pallet in the enclosure formed by the vertical walls by a compression plate.
 9. The method of claim 6, comprising selecting, by the programmable controller, the first and second amounts of product to be filed in the first bag and in the second bag respectively, from a batching supply.
 10. The method of claim 6, comprising an operator positioning the first bag with an open mouth and activating feeding of the first amount of product within the first bag, and an operator positioning the second bag with an open mouth and activating feeding of the second amount of product within the second bag.
 11. The method of claim 6, wherein said filing the first bag comprises shaking the first bag and guiding the first bag into a shape footprint corresponding to the pallet using guiding plates.
 12. The method of claim 6, comprising, before said depositing the second bag filled with the second amount of product on top of the first bag filled with the first amount of product, compacting a positioning hole in a top surface of the first bag.
 13. The method of claim 6, comprising filling the second bag, lifting up the filled second bag, positioning the filled first bag underneath the filled second bag, and depositing the second bag filled with the second amount of product on top of the first bag on the pallet.
 14. A bag straightener, comprising: vertical walls; and a top compression plate; wherein said walls are controlled by cylinders into moving from an opened position, to receive a bag, to an enclosure position around the bag; and said compression plate is then actuated by a compaction cylinder operating a compaction shaft supporting the compression plate into compressing the bag in the enclosure formed by said walls. 